Reproduction Sheet Metal Demystified

There are many opinions regarding the current state of
quality of aftermarket sheet metal for restoration purposes and while some of
those opinions are fact-based, many misconceptions exist which can cloud the
issue. So here are some facts which may
help people better understand

To begin with, metal stamping is a process that has a large
number of variables that must be controlled to make dimensionally correct parts
on a repeatable basis. Contrary to
popular belief, parts as complex as body panels are not stamped with a die of
fixed geometry so that the part will be the same all the time. Today, as in the 60’s and 70’s, dies are complex
machines themselves - with moving parts and those parts that must be
maintained. Steel used to make parts can differ coil to coil in
the gauge, camber, cross bow, buckles, etc. Settings and control of the stamping machines
as well as the skill of the die setup crew also contribute greatly to part quality. Frankly it was back in the day and is today a
miracle that part dimensions can be repeatable at all. Said another way, it is very possible to take
a die and make parts one day and the next day using the same die have parts
that differ as much as ¼” on a large part like a body panel. Finally, dies do wear with time, so details
like body lines tend to become obscured over time naturally. With all that said, sheet metal of the 60’s
and 70’s had as much – and likely more variability than that of metal stamped
today because the quality systems today are much further advanced.

Couple this with how bodies were assembled in the 60’s and
70’s – many were man-handled to fit in the fixtures when welded up, so the
bodies themselves had variability when assembled (much more so than
today). Subject the assembled car to 45+
years of wear and tear and even putting pristine NOS sheet metal on it today
can pose challenges.

A remaining question is who made / owns the tooling that
makes the sheet metal parts for the aftermarket? It is probable that it is a combination; some
of the marketers like AMD, Dynacorn, Goodmark, etc. own some of their own tools
as well as buy parts from tools owned by the metal stamper. In today’s world of stamped metal parts most
of the time the buyer of the part specifies the geometry and the stamper has
the tool built for the customer and charges him for it (either in total, or
amortizes the cost over “X” number of
parts sold to the customer). It’s
possible, but not typical for a customer to supply a tool especially to an overseas
stamper.

Now many people are concerned about the current aftermarket
sheet metal source, feeling that “cheap Asian” sheet metal is the problem. This really isn’t true - certainly any
company can (and does) make bad product from time to time, but it isn’t
rational for a business to consistently make and sell sub-par quality as a
basis for a business model. Today there
are a handful of companies serving the aftermarket sheet metal for
restorers. In the US the well known ones
are Auto Metal Direct (AMD) Dynacorn (DII), Goodmark and Sherman &
Associates. There is a perception that
some or all make their own parts to sell.
This isn’t the case; none of these companies currently stamp their own sheet
metal in the US. They all source their
parts to Taiwanese companies who mostly stamp in Taiwan, but may also then
sub-contract to facilities in China.

Those companies in Taiwan that produce aftermarket sheet
metal parts are CHL Autoparts, TriPlus, He Qing Industry Co., LTD, Golden
Legion Automotive Corp. and Shyi Tan Enterprises Co, LTD. These companies sell to most of the marketers
of sheet metal in the US and many marketers sell the same part as their
own. It is not uncommon to find stickers
on parts that carry many different part numbers on them that represent Goodmark
and Sherman as an example. While some of
these marketers may own the tool that produced the part, it is more than likely
that the metal stamper had to the tool built and is amortizing the tool cost in
each piece they produce. The larger
number of parts made on a tool, the more cost effective the tool becomes.

Each marketer may have their own quality control process
which may be a point of differentiation, so it is possible that parts from say
Goodmark show better than say Sherman because Goodmark inspected the parts that
were imported more thoroughly than Sherman and therefore culled out any
off-spec parts before retailing them in the US market. NOTE – THIS IS FOR EXAMPLE ONLY, WE MAKE NO
JUDGEMENT ON THE QUALITY OF ANY MARKETER’S PARTS.

In the end, when you buy an AMD, Dynacorn, Goodmark or
Sherman for the most part you are buying a part made by one of the following
metal stampers: CHL Automotive, TriPlus,
Golden Legion Automotive Corp, Shyi Tan Enterprises CO LTD or He Qing Industry
CO, LTD. They are all good companies,
based in Taiwan and sell to most all of the marketers of aftermarket sheet
metal in the US on a non-exclusive basis.